The present invention relates to a hydroxyphenyl derivatives which have HIV integrase inhibitory properties that have been characterized by specific structural and physicochemical features. This inhibitory property may be advantageously used, for example, to provide medicinals (e.g. compositions) with antiviral properties against HIV viruses, including the HIV-1 and HIV-2 viruses, i.e. the hydroxyphenyl derivatives including pharmaceutical compositions thereof may be used to inhibit the activity of HIV integrase.
The HIV (human immunodeficiency virus) retrovirus is the causative agent for AIDS (acquired immunodeficiency syndrome). Thus the HIV-1 retrovirus primarily uses the CD4 receptor (a 58 kDa transmembrane protein) to gain entry into cells, through high-affinity interactions between the viral envelope glycoprotein (gp 120) and a specific region of the CD4 molecule found in T-lymphocytes and CD4 (+) T-helper cells (Lasky L. A. et al., Cell vol. 50, p. 975-985 (1987)). HIV infection is characterized by a period immediately following infection called xe2x80x9casymptomaticxe2x80x9d which is devoid of clinical manifestations in the patient. Progressive HIV-induced destruction of the immune system then leads to increased susceptibility to opportunistic infections, which eventually produces a syndrom called AIDS-related complex (ARC) characterized by symptoms such as persistent generalized lymphadenopathy, fever, weight loss, followed itself by full blown AIDS. After entry of the retrovirus into a cell, viral RNA is converted into DNA, which is then integrated into the host cell DNA. The reverse transcriptase encoded by the virus genome catalyzes the first of these reactions (Haseltine W. A. FASEB J. vol 5, p. 2349-2360 (1991)). At least three functions have been attributed to the reverse transcriptase: RNA-dependent DNA polymerase activity which catalyzes the synthesis of the minus strand DNA from viral RNA, ribonuclease H (RNase H) activity which cleaves the RNA template from RNA-DNA hybrids and DNA-dependent DNA polymerase activity which catalyzes the synthesis of a second DNA strand from the minus strand DNA template (Goff S. P. J. Acq. Imm. Defic. Syndr. Vol 3, p. 817-831 (1990)). The double stranded DNA produced by reverse transcriptase, now called provirus, is then able to be inserted into host genomic DNA. At the end of reverse transcription, the viral genome now in the form of DNA is integrated into host genomic DNA and serves as a template for viral gene expression by the host transcription system, which leads eventually to virus replication (Roth et al.,1989). The preintegration complex consists of integrase, reverse transcriptase, p17 and proviral DNA (Bukrinsky M. I., Proc. Natn. Acad. Sci. USA vol. 89 p.6580-6584 (1992)). The phosphorylated p17 protein plays a key role in targeting the preintegration complex into the nucleus of host cell (Gallay et al., 1995).
The primary RNA transcripts made from the provirus are synthesized by the host cell RNA polymerase II which is modulated by two virus-encoded proteins called tat and rev. The viral proteins are formed as polyproteins.
Post-translational modifications of viral polyproteins include processing and glycosylation of Env (envelope) proteins, and myristylation of the N-terminal residue of the p17 protein in the Gag and Gag-Pol polyproteins. The latter two precursors correspond to structural proteins and viral enzymes. The viral protease is involved in processing polyproteins Gag and Gag-Pol into mature proteins, a step essential for virus infectivity.
A number of synthetic antiviral agents have been designed to block various stages in the replication cycle of HIV. These agents include compounds which interfere with viral binding to CD4 T-lymphocytes (for example, soluble CD4), compounds which block viral reverse transcriptase (for example, didanosine and zidovudine (AZT)), budding of virion from the cell (interferon), or the viral protease (for example Ritonavir and Indinavir). Some of these agents proved ineffective in clinical tests. Others, targeting primarily early stages of viral replication, have no effect on the production of infectious virions in chronically infected cells. Furthermore, administration of many of these agents in effective therapeutic doses has led to cell-toxicity and unwanted side effects, such as anemia, neurotoxicity and bone marrow suppression. Anti-protease compounds in their present form are typically large and complex molecules of peptidic nature that tend to exhibit poor bioavailability and are not generally consistent with oral administration. These compounds often exhibit side effects such as nausea, diarrhea, liver abnormalities and kidney stones.
Accordingly, the need exists for compounds that can effectively inhibit the action of the third viral enzyme called integrase, for use as agents for treating HIV infections.
The terms HIV integrase and integrase as used herein are used interchangeably and refer to the integrase enzyme encoded by the human immunodeficiency virus type 1 or 2. In particular this term includes the human immunodeficiency virus type 1 integrase.
The present invention provides an hydroxyphenyl derivative selected from the group consisting of a compound of formula 
and when a compound of formula I comprises a carboxylic acid group pharmaceutically acceptable salts thereof and when a compound of formula I comprises an amino group pharmaceutically acceptable ammonium salts thereof, wherein n is 1, 2 or 3, e is 1, 2 or 3, Hal represents a halogen atom (e.g. Cl, Br, F or I), p is 0, 1 or 2, r is 0, 1 or 2, X and Xxe2x80x2 each independently represents a single bond, a saturated straight or branched hydrocarbon group of 1 to 4 carbon atoms or a straight or branched hydrocarbon group of 2 to 4 carbon atoms comprising a carbon to carbon double bond, Ra represents H or xe2x80x94CH3, and Raa represents H or xe2x80x94CH3; W, may for example, represent an amino acid residue or fragment (in particular alpha-amino acid residues) such as for example a residue based on tyrosine, DOPA, hydroxyproline, serine, threonine, histidine, valine, phenylalanine, lysine, alanine, glycine, glutamic acid, aspartic acid, arginine, asparagine, glutamine, leucine, lysine, isoleucine, proline, tryptophan, methionine, cysteine, cystine, thyroxine, meta-tyrosine, sarcosine, other alpha-methyl amino acids such as alpha-methyl DOPA, as well as other 3-substituted tyrosines, and the like.
W, for the above formula I, may, for example, be derived from natural or unnatural alpha-amino acids. The term unnatural alpha-amino acid refers to alpha-amino acids which do not occur in nature but which can be derived from naturally occurring alpha-amino acids or other chemical reagents by methods known to those skilled in the art.
W may, for example, represent a group of formula 
wherein k is 0 or 1, A and Axe2x80x2 each independently represents a group of formula 
Ra represents H or xe2x80x94CH3, Rb represents H or xe2x80x94CH3, Rc represents H or OH, R is selected from the group consisting of H, CH3xe2x80x94, (CH3)2CHxe2x80x94, (CH3)2CHCH2xe2x80x94, CH3CH2CH(CH3)xe2x80x94, C6H5CH2xe2x80x94, CH3SCH2CH2xe2x80x94, HO2CCH2xe2x80x94, H2NC(O)CH2xe2x80x94, HO2CCH2CH2xe2x80x94, H2NC(O)CH2CH2xe2x80x94, H2NCH2CH2CH2CH2xe2x80x94, HOCH2xe2x80x94, CH3CH(OH)xe2x80x94, HSCH2xe2x80x94, HO2Cxe2x80x94, benzyloxycarbonyl, benzyloxycarbonylmethyl, 
wherein Hal is as defined above and f is 0, 1 or 2, g is 0, 1 or 2, and each q is independently 0 or 1.
The group of structure 
may in particular for example be a fluoride substituted structure of formula 
Similarly, the group of structure 
may in particular for example be a fluoride substituted structure of formula 
As mentioned, when a compound of formula I comprises a carboxylic acid group the polyhydroxy compounds may be any pharmaceutically acceptable salt thereof and when a compound of formula I comprises an amino group the polyhydroxy compounds may be any pharmaceutically acceptable ammonium salt thereof.
The present invention provides, where appropriate, salts (e.g. derived from appropriate bases or acids) which include but are not limited to alkali metal (e.g., sodium, potassium, cesium, etc.) salts, alkaline earth metal (e.g., magnesium) salts, and ammonium salts such as acid addition salts of amines (e.g. ammonium chloride salts) as well as quaternary ammonium salts of for example Nxe2x80x94(Rxe2x80x3)4+ type wherein Rxe2x80x3 is an organic residue.
The pharmaceutically acceptable salts of the compounds of this invention include those derived from pharmaceutically acceptable inorganic and organic acids and bases. Examples of such acid salts include: acetate adipate, alginate aspartate benzoate, benzenesulfonate, bisulfate, butyrate, citrate, camphorate, camphorsulfonate, cyclopentanepropionate, digluconate, dodecylhydrogen-sulfate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptanoate, glycerophosphate, glycollate, hemisulfate, heptanoate, hexanoate, hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethanesulfonate, lactate, maleate, malonate, methanesulfonate, 2-naphthylsulfonate, nicotinate, nitrate, oxalate, pamoate, pectinate, perchlorate, persulfate, 3-phenylpropionate, phosphate, picrate, pivalate, propionate, salicylate, succinate, sulfate, tartrate, thiocyanate, tosylate, and undecanoate.
This invention also envisions the quaternization of any basic nitrogen containing groups of the compounds disclosed herein. The basic nitrogen can be quaternized with any agents known to those of ordinary skill in the art including, for example, lower alkyl halides, such as methyl, ethyl, propyl and butyl chloride, bromides and iodides; dialkyl sulfates including dimethyl, diethyl, dibutyl and diamyl sulfates; long chain halides such as decyl, lauryl, myristyl and stearyl chlorides, bromides and iodide; and arylalkyl halides including benzyl and phenethyl bromides. Water or oil-soluble or dispersible products may be obtained by such quaternization.
This invention also envisions the presence of an ester group(s) such as for example on the acidic end of an appropriate amino acid fragment(s), such as glutamic acid and aspartic acid as having some anti-integrase activity as such as acting as pro-drugs, i.e. capable of hydrolysis of the ester moiety to liberate in the systemic circulation the acid, also possessing anti-integrase activity. For example, the ether oxygen of an ester compound may be attached or linked to benzyl, a lower (branched or straight) alkyl (e.g. C1-C6 alkyl) such as methyl, a lower cycloalkyl (e.g. C3-C7 cycloalkyl) such as cyclohexyl, and the like. Alternatively, an ester(s) may be derived from a carboxylic acid(s) and one or more hydroxyl groups, such as for example an hydroxyl group on a phenyl ring. A carboxylic acid may, for example, comprise an acyl group having from 2 to 8 carbon atoms; the acyl group may for example comprise lower alkyl of 1 to 6 carbon atoms, lower cycloalkyl of from 3 to 7 carbon atoms, etc..
In addition, this invention further envisions the presence of structures having an amide functionality such as, for example, on the carboxylic end located on the side chain of such acids. These amides, such as simple primary, secondary or tertiary amides, possess activity of their own. In addition, it is possible to couple such acids with dopamine to yield compounds of interest. The amino moiety of an amide compound may for example be xe2x80x94NH2, xe2x80x94NH(C1-C6 alkyl), or xe2x80x94N(C1-C6 alkyl)2, a pyrrolidine residue, a piperidine residue, a morpholine residue and the like
In any event, it is also to be understood that the present invention relates to any other compound having a structure such that, upon administration to a recipient, it is capable of providing (directly or indirectly) a compound of this invention or an antivirally active metabolite or residue thereof. Thus the compounds of this invention may be modified by appending appropriate functionalities to enhance selective biological properties. Such modifications are known in the art and include those which increase biological penetration into a given biological system (e.g., blood, lymphatic system, central nervous system), increase oral availability, increase solubility to allow administration by injection, alter metabolism and alter rate of excretion.
The present invention in particular provides a dopamine derivative selected from the group consisting of a compound of formula Ia 
and when a compound of formula Ia comprises a carboxylic acid group pharmaceutically acceptable salts thereof and when a compound of formula Ia comprises an amino group pharmaceutically acceptable ammonium salts thereof, wherein n, Ra and R are as defined above.
The present invention also provides a dopamine derivative selected from the group consisting of a compound of formula Ib 
wherein n is as defined above (e.g. n may in particular be 1 or 2), and Rd is selected from the group consisting of H and OH.
The present invention further relates to dipeptide derivatives i.e. to compounds of formula I defined above wherein k is 1. The present invention in particular provides an hydroxylphenyl derivative wherein for the compound of general formula I above, W represents a group of formula 
wherein n is as defined above (e.g. n may in particular be 1 or 2), p is as defined above (p may in particular be 0), each Ra is independently as defined above, each Rb is independently as defined above, and each R is independently as defined above; more particularly, for example, for each R, f may be 0 or 1 and g may be 0 or 1.
The compounds of this invention contain one or more asymmetric carbon atoms and thus may occur as racemates and racemic mixtures, single enantiomer, diastereomeric mixtures and individual diastereoisomers. All such isomeric forms of these compounds are expressly included in the present invention. Each stereogenic carbon may be of the R or S configuration.
The amino acid residues may, for example, in any event, be of L, D or DL form, preferably of L form; thus for example the amino acid residue (i.e. W) may be a L-xcex1-amino residue, a D-xcex1-amino residue, or a DL-xcex1-amino residue.
Accordingly, the present invention further provides a dopamine derivative selected from the group consisting of a compound of formula Ic 
and when a compound of formula Ic comprises a carboxylic acid group pharmaceutically acceptable salts thereof and when a compound of formula Ic comprises an amino group pharmaceutically acceptable ammonium salts thereof,
wherein n is 1, or 2, Ra and R are as defined above (e.g. f and g may be 0 or 1 and the respective group Hal thereof may be fluorine (F)).
The present invention furthermore provides a dopamine derivative selected from the group consisting of a compound of formula Id 
and when a compound of formula Id comprises a carboxylic acid group pharmaceutically acceptable salts thereof and when a compound of formula Id comprises an amino group pharmaceutically acceptable ammonium salts thereof, wherein n is 1, or 2, each Ra is independently as defined above, and each R is independently as defined above; more particularly, for example, for each R, f may be 0 or 1 and g may be 0 or 1.
The compounds of the present invention including where applicable their pharmaceutically acceptable derivatives have an affinity for integrase, in particular, HIV integrase. Therefore, these compounds are useful as inhibitors of such integrase, i.e. they are in particular useful as HIV integrase inhibitors. These compounds can be used alone or in combination with other therapeutic or prophylactic agents, such as antivirals, antibiotics, immunomodulators or vaccines, for the treatment or prophylaxis of viral infection.
According to the present invention, the compounds of this invention are capable of inhibiting HIV viral replication in human CD4+ T-cells, by inhibiting the ability of HIV integrase to integrate the double stranded DNA into host genomic DNA for further virus replication by the host cell machinery (Sakai H., J. Virol. Vol. 67 p. 1169-1174 (1993)). These novel compounds can thus serve to reduce the production of infectious virions from acutely infected cells, and can inhibit the initial or further infection of host cells. Accordingly, these compounds are useful as therapeutic and prophylactic agents to treat or prevent infection by HIV-1 and related viruses, which may result in asymptomatic HIV-1 infection, AIDS-related complex (ARC), acquired immunodeficiency syndrome (AIDS), AIDS-related dementia, or similar diseases of the immune system.
Thus the present invention also provides a pharmaceutical composition comprising a pharmaceutically acceptable carrier and a pharmaceutically effective amount of at least one hydroxyphenyl derivative as defined above. The pharmaceutical compositions may be used to inhibit integrase, including HIV integrase, thus providing protection against HIV infection.
The expression xe2x80x9cpharmaceutically effective amountxe2x80x9d is to be understood herein as referring to an amount effective in treating HIV infection in a patient. The term prophylactically effective amount refers to an amount effective in preventing HIV infection in a patient. As used herein, the term patient refers to a mammal, including a human. The expressions xe2x80x9cpharmaceutically acceptable carrierxe2x80x9d (or adjuvant) and xe2x80x9cphysiologically acceptable vehiclexe2x80x9d are to be understood as referring to a non-toxic carrier or adjuvant that may be administered to a patient, together with a compound of this invention, and which does not destroy the pharmacological activity thereof. These factors will be discussed in more detail below.
The compounds of this invention may be readily prepared using conventional techniques from commercially available and cheap starting materials. The relative ease of synthesis of the products described in this invention represents a marked advantage for the large scale preparation of these compounds. In general, the derivatives of the present invention may be readily obtained from amino acids through sequences recognized by those knowledgeable in the art as straightforward, requiring readily available reagents and easy techniques. Using standard techniques, amino acids may be transformed to the desired HIV integrase inhibitors according to approaches as shown in Scheme 1, Scheme 2 and Scheme 3 which are discussed below. The preparation of dipeptide derivatives may be accomplished by solid phase peptide synthesis; this type of process is generically illustrated in scheme 4 below (see example 42 below).
Scheme 1 illustrates example steps for the preparation of a derivative in accordance with the present invention:
Note:
a) For scheme 1, PG and PGxe2x80x2 may be any suitable (known) removable protecting group for respectively protecting the amine functional group and the carboxylic acid functional group(s). PG may, for example, be Boc i.e. tert-butoxycarbonyl and PGxe2x80x2 may, for example, be tert-Butyl, 2,6-Cl2Bzl or Bzl, i.e. a functional group of the following formula 
b) For scheme 1 R1 may, for example, be CH3xe2x80x94, BzlOOCCH2CH2xe2x80x94, H2NC(O)CH2CH2xe2x80x94; R1a may, for example, be CH3xe2x80x94, HOOCCH2CH2xe2x80x94, H2NC(O)CH2CH2xe2x80x94
Step 1) 
Step 2) 
Step 3) 
Step 4) 
Step 5) 
In accordance with Scheme 1, illustrated above, different pharmacophores may be attached to the amino acid via the N-terminal. Thus, for step 1 compound 1 is treated so as to protect the carboxylic acid functional group by means of a suitable protecting group PGxe2x80x2; for example compound 1 may be a Boc-amino acid which is benzylated with benzyl bromide to yield compound 2 in the form of a benzyl ester using cesium carbonate in DMF according to the method of S.-S. Wang et al (J. Org. Chem. vol 49 p. 1286 (1977)). For step 2 the amino protecting group PG is removed to provide compound 3 having a free amino functional group; for example the removal of the Boc group from compound 3 may be carried out by stirring in a mixture of TFA and methylene chloride (1:1 (v/v)). For step 3 the amino compound 3 is then coupled with an hydroxylated benzoic acid (compound 4) with EDC and HOBT in DMF providing the desired coupled product compound 5. For step 4 compound 5 is treated to remove the protecting group PGxe2x80x2 to yield compound 6 having a free carboxylic acid group; for example the benzyl protecting group PGxe2x80x2 may be removed by hydrogenolysis using 10% Pd/C as catalyst to yield compound 6 having a free carboxylic acid group. Finally for step 5 compound 6 is coupled with dopamine (compound 7) to provide the desired derivative, namely compound 8.
Scheme 2 (which is divided below into scheme 2a and scheme 2b) illustrates example steps for an alternate method for the preparation of a derivative in accordance with the present invention:
Note:
a) For scheme 2a, PG, as mentioned above, may be any suitable (known) removable protecting group for protecting the amine functional group. PG may, for example, be Boc i.e. tert-butoxycarbonyl
b) For scheme 2a, R3 may, for example, be (CH3)2CHCH2xe2x80x94, CH3SCH2CH2xe2x80x94, or a functional group of the following formula 
Scheme 2a:
Step 1 
Step 2: 
Step 3: 
Scheme 2b:
Step 1 
Step 2: 
Step 3: 
The second approach illustrated in scheme 2 above proceeds by the C-terminal first with the subsequent coupling taking place at a later stage after the removal of the amino blocking group. Thus, for step 1 of scheme 2a compound 1 (e.g. a Boc amino acid) is coupled with dopamine (compound 9) using EDC and HOBT as coupling reagents in DMF to obtain compound 10. For step 2 of scheme 2a compound 10 is treated to remove the protecting or blocking group PG to obtain compound 11; for example, the removal of a Boc group may be performed by stirring compound 10 in a mixture of TFA and methylene chloride at room temperature for a short period of time. For step 3 of scheme 2a compound 11 may then be coupled with the appropriate hydroxybenzoic acid (compound 4) using the EDC/HOBT coupling conditions to obtain compound 12. The desired product compound 12 may then be deprotected if needed or appropriate by hydrogenolysis using 10% Pd/C as catalyst for those amino acid with functionality on the side chain. Scheme 2b may proceed in an analogous fashion.
Scheme 3 illustrates yet another example method for the preparation of a derivative in accordance with the present invention
Note:
a) For scheme 3, PG and PGxe2x80x3 may be any suitable (known) independently removable protecting group for respectively protecting different functional groups including a nitrogen atom. PG may, for example, be Boc i.e. tert-butoxycarbonyl and PGxe2x80x3 may, for example, be Fmoc, i.e. 9-fluorenylmethoxycarbonyl
b) For scheme 3, R4 may, for example, be xe2x80x94HNCH2CH2CH2xe2x80x94 or a group of formula 
and R5 may, for example, be H2NCH2CH2CH2xe2x80x94 or a group of formula 
Step 1 
Step 2 
Step 3: 
Step 4: 
In scheme 3 illustrated above the starting amino acid (compound 13) is provided with a pair of independently removable protecting groups PG and PGxe2x80x3; the amino group may have a protecting group (PGxe2x80x3) such as Fmoc for example. On the other hand if the group R4 includes a primary or secondary amino component a protecting group PG may likewise be attached to the nitrogen atom of such an amino component; PG may, for example, be Boc or tert-butoxycarbonyl. Thus, for step 1 of scheme 3 compound 13 is coupled with dopamine (compound 9) using EDC and HOBT as coupling reagents in DMF to obtain compound 14. For step 2 compound 14 is treated to remove the protecting or blocking group PGxe2x80x3 to obtain compound 15. For step 3 compound 15 may then be coupled with the appropriate hydroxybenzoic acid (compound 4) using the EDC/HOBT coupling conditions to obtain compound 16. For step 4 compound 15 is treated to remove the protecting group PG to yield compound 17.
Scheme 4 illustrates in a generic fashion an example method for the preparation of a dipeptide derivative in accordance with the present invention (see example 42 below for a more specific description of a process for making a dipeptide derivative):
Step 1 
xe2x80x83(RX and RXxe2x80x2 independently have the values set forth for R herein).
The compounds listed in Table 1 were prepared by following Scheme 1 or Scheme 2 (see examples below); the number(s) in brackets after each root amino acid name is the numer(s) of an example(s) below. Their activities are also listed in the same table demonstrating their potential usefulness.
Dipeptide derivatives were also prepared and are listed in Table 2; the number(s) in Table 2 with respect to each product structure name therein indicated a number of an example.
As can be appreciated by the skilled artisan, the above synthetic schemes are not intended to comprise a comprehensive list of all means by which the compounds described and claimed in this application may be synthesized. Further methods will be evident to those of ordinary skill in the art.
For the purposes of Table 1 (and Table 2) the HIV-1 integrase inhibition assay was carried out following a known procedure (Burke, Jr. T. R. et al., J. Med. Chem. 38, 4171-4178 (1995)). A suitable radiolabeled duplex substrate corresponding to the U5 end of the HIV LTR was used.
The novel compounds of the present invention are excellent ligands for integrase, particularly HIV-1, and most likely HIV-2 and HTLV-1 integrase. Accordingly, these compounds are capable of targeting and inhibiting an early stage event in the replication, i.e. the integration of viral DNA into the human genome, thus preventing the replication of the virus.
In addition to their use in the prophylaxis or treatment of HIV infection, the compounds according to this invention may also be used as inhibitory or interruptive agents for other viruses which depend on integrases, similar to HIV integrases, for obligatory events in their life cycle. Such compounds inhibit the viral replication cycle by inhibiting integrase. Because integrase is essential for the production of mature virions, inhibition of that process effectively blocks the spread of virus by inhibiting the production and reproduction of infectious virions, particularly from acutely infected cells. The compounds of this invention advantageously inhibit enzymatic activity of integrase and inhibit the ability of integrase to catalyze the integration of the virus into the genome of human cells.
The compounds of this invention may be employed in a conventional manner for the treatment or prevention of infection by HIV and other viruses which depend on integrases for obligatory events in their life cycle. Such methods of treatment, their dosage levels and requirements may be selected by those of ordinary skill in the art from available methods and techniques. For example a compound of this invention may be combined with a pharmaceutically acceptable adjuvant for administration to a virally infected patient in a pharmaceutically acceptable manner and in an amount effective to lessen the severity of the viral infection. Also, a compound of this invention may be combined with pharmaceutically acceptable adjuvants conventionally employed in vaccines and administered in prophylactically effective amounts to protect individuals over an extended period of time against viral infections, such as HIV infection. As such, the novel integrase inhibitors of this invention can be administered as agents for treating or preventing viral infections, including HIV infection, in a mammal. The compounds of this invention may be administered to a healthy or HIV-infected patient either as a single agent or in combination with other antiviral agents which interfere with the replication cycle of HIV. By administering the compounds of this invention with other antiviral agents which target different events in the viral replication cycle, the therapeutic effect of these compounds is potentiated. For instance, the co-administered antiviral agent can be one which targets early events in the life cycle of the virus, such as cell entry, reverse transcription and viral DNA integration into cellular DNA. Antiviral agents targeting such early life cycle events include, didanosine (ddI), zalcitabine (ddC), stavudine (d4T), zidovudine (AZT), polysulfated polysaccharides, sT4 (soluble CD4)xe2x80x94which blocks attachment or adsorption of the virus to host cellsxe2x80x94and other compounds which block binding of virus to CD4 receptors on CD4-bearing T-lymphocytes. Other retroviral reverse transcriptase inhibitors, such as derivatives of AZT, may also be co-administered with the compounds of this invention to provide therapeutic treatment for substantially reducing or eliminating viral infectivity and the symptoms associated therewith. Examples of other antiviral agents include ganciclovir, dideoxycytidine, trisodium phosphonoformiate, eflornithine, ribavirin, acyclovir, alpha interferon and trimenotrexate. Additionally, non-ribonucleoside inhibitors of reverse transcriptase, such as TIBO or nevirapine, may be used to potentiate the effect of the compounds of this invention, as may viral uncoating inhibitors, inhibitors of trans-activating proteins such as tat or rev, or inhibitors of the viral protease. These compounds may also be co-administered with other inhibitors of HIV integrase.
Combination therapies according to this invention exert a synergistic effect in inhibiting HIV replication because each component agent of the combination acts on a different site of HIV replication. The use of such combinations also advantageously reduces the dosage of a given conventional anti-retroviral agent that would be required for a desired therapeutic or prophylactic effect as compared to when that agent is administered as a monotherapy. These combinations may reduce or eliminate the side effects of conventional single anti-retroviral agent therapies while not interfering with the anti-retroviral activity of those agents. These combinations reduce potential of resistance to single agent therapies, while minimizing any associated toxicity. These combinations may also increase the efficacy of the conventional agent without increasing the associated toxicity. Preferred combination therapies include the administration of a compound of this invention with AZT, 3TC, ddI, ddC or d4T.
Alternatively, the compounds of this invention may also be co-administered with other HIV protease inhibitors such as Ro 31-8959 (Roche), L-735,524 (Merck), XM 323 (Dupont Merck) and A-80,987 (Abbott) to increase the effect of therapy or prophylaxis against various viral mutants or members of other HIV quasi species.
We prefer administering the compounds of this invention as single agents or in combination with retroviral reverse transcriptase inhibitors, such as derivatives of AZT or HIV aspartyl protease inhibitors. We believe that the co-administration of the compounds of this invention with retroviral reverse transcriptase inhibitors or HIV aspartyl protease inhibitors may exert a substantial synergistic effect, thereby preventing, substantially reducing, or completely eliminating viral infectivity and its associated symptoms.
The compounds of this invention can also be administered in combination with immunomodulators (e.g., bropirimine, anti-human alpha interferon antibody, IL-2, GM-CSF, methionine enkephalin, interferon alpha, diethyldithiocarbante, tumor necrosis factor, naltrexone and rEPO); antibiotics (e.g., pentamidine isethionate) or vaccines to prevent or combat infection and disease associated with HIV infection, such as AIDS and ARC.
When the compounds of this invention are administered in combination therapies with other agents, they may be administered sequentially or concurrently to the patient. Alternatively, pharmaceutical or prophylactic compositions according to this invention may be comprised of a combination of an integrase inhibitor of this invention and another therapeutic or prophylactic agent.
Although this invention focuses on the use of the compounds disclosed herein for preventing and treating HIV infection, the compounds of this invention can also be used as inhibitory agents for other viruses that depend on similar integrases for obligatory events in their life cycle. These viruses include, but are not limited to, other diseases caused by retroviruses, such as simian immunodeficiency viruses, HTLV-I and HTLV-II.
Pharmaceutical compositions of this invention comprise any of the compounds of the present invention, and pharmaceutically acceptable salts thereof, with any pharmacentically acceptable carrier, adjuvant or vehicle. Pharmaceutically acceptable carriers, adjuvants and vehicles that may be used in the pharmaceutical compositions of this invention include, but are not limited to ion exchangers, alumina, aluminum stearate, lecithin, serum proteins, such as human serum albumin, buffer substances such as phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, water, salts or electrolytes, such as protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinyl pyrrolidone, cellulose-based substances, polyethyleneglycol, sodium carboxymethylcellulose, polyacrylates, waxes, polyethylene-polyoxypropylene-block polymers, polyethylene glycol and wool fat.
The pharmaceutical compositions of this invention may be administered orally, parenterally by inhalation spray, topically, rectally, nasally, buccally, vaginally or via an implanted reservoir. We prefer oral administration or administration by injection. The pharmaceutical compositions of this invention may contain any conventional non-toxic pharmaceutically acceptable carriers, adjuvants or vehicles. The term xe2x80x9cparenteralxe2x80x9d as used herein includes subcutaneous, intracutaneous, intravenous, intramuscular, intra-articular, intrasynovial, intrasternal, intrathecal, intralesional and intracranial injection or infusion techniques.
The pharmaceutical compositions may be in the form of a sterile injectable preparation, for example, as a sterile injectable aqueous or oleaginous suspension. This suspension may be formulated according to techniques known in the art using suitable dispersing or wetting agents (such as, for example, Tween 80) and suspending agents. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are mannitol, water, Ringer""s solution and isotonic sodium chloride solutions. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose, any bland fixed oil may be employed including synthetic mono- or diglycerides. Fatty acids, such as oleic acid and its glyceride derivatives are useful in the preparation of injectables, as are natural pharmaceutically-acceptable oils, such as olive oil or castor oil, especially in their polyoxyethylated versions. These oil solutions or suspensions may also contain a long-chain alcohol diluent or dispersant, such as Ph. Helv. or a similar alcohol.
The pharmaceutical compositions of this invention may be orally administered in any orally acceptable dosage form including, but not limited to, capsules, tablets, and aqueous suspension and solutions. In the case of tablets for oral and carriers which are commonly used include lactose and corn starch. Lubricating agents, such as magnesium stearate, are also typically added. For oral administration in a capsule form, useful diluents include lactose and dried corn starch. When aqueous suspensions are administered orally, the active ingredient is combined with emulsifying and suspending agents. If desired, certain sweetening and/or flavoring and/or coloring agents may be added.
The pharmaceutical compositions of this invention may also be administered in the form of suppositories for rectal administration. These compositions can be prepared by mixing a compound of this invention with a suitable non-irritating excipient which is solid at room temperature but liquid at the rectal temperature and therefore will melt in the rectum to release the active components. Such materials include, but are not limited to, cocoa butter, beeswax, and polyethylene glycols.
Topical administration of the pharmaceutical compositions of this invention is especially useful when the desired treatment involves areas or organs readily accessible by topical application. For application topically to the skin, the pharmaceutical composition should be formulated with a suitable ointment containing the active components suspended or dissolved in a carrier. Carriers for topical administration of the compounds of this invention include, but are not limited to, mineral oil, liquid petroleum, white petroleum, propylene glycol, polyoxyethylene polyoxypropylene compound, emulsifying wax and water. Alternatively, the pharmaceutical compositions can be formulated with a suitable lotion or cream containing the active compound suspended or dissolved in a carrier. Suitable carriers include, but are not limited to mineral oil, sorbitan monostearate, polysorbate 60, cetyl esters wax cetearyl alcohol, 2-octyldodecanol, benzyl alcohol and water. The pharmaceutical compositions of this invention may also be topically applied to the lower intestinal tract by rectal suppository formulation or in a suitable neat formulation. Topically-transdermal patches are also included in this invention.
The pharmaceutical compositions of this invention may be administered by nasal aerosol or inhalation. Such compositions are prepared according to techniques well-known in the art of pharmaceutical formulation and may be prepared as solutions in saline employing benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, fluorocarbons, and/or other solubilizing or dispersing agents known in the art.
Dosage levels of between about 0.01 and about 25 mg/kg body weight per day, preferably between about 0.5 and about 25 mg/kg body weight per day of the active ingredient compound are useful in the prevention and treatment of viral infection, including HIV infection. Typically, the pharmaceutical compositions of this invention will be administered from about 1 to about 5 times per day or alternatively, as a continuous infusion. Such administration can be used as a chronic or acute therapy. The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the patient treated and the particular mode of administration. A typical preparation will contain from about 5% to about 75% active compound (w/w). Preferably, such preparations contain from about 20% to about 50% active compound.
Upon improvement of a patient""s condition, a maintenance dose of a compound, composition or combination of this invention may be administered if necessary. Subsequently, the dosage or frequency of administration, or both, may be reduced, as a function of the symptoms, to a level at which the improved condition is retained. When the symptoms have been alleviated to the desired level, treatment should cease, at least in principle. Patients may, however, require intermittent treatment on a long-term basis, upon any recurrence of disease symptoms, especially for AIDS.
As the skilled artisan will appreciate, lower or higher doses than those recited above may be required. Specific dosage and treatment regimen for any particular patient will depend upon a variety of factors, including the activity of the specific compound employed, the age, body weight, general health status, sex, diet, time of administration, rate of excretion, drug combination, the severity and course of the infection, the patient""s disposition to the infection and the judgment of the treating physician.
The compounds of this invention are also useful as commercial reagents which effectively bind to integrases, particularly HIV integrase. As commercial reagent, the compounds of this invention, and their derivatives, may be used to block integration of a target DNA molecule by integrase, or may be derivatized to bind to a stable resin as a tethered substrate for affinity chromatography applications. These and other uses which characterize commercial integrase inhibitors will be evident to those of ordinary skill in the art.
In order that the invention herein described may be more fully understood, the following detailed description is set forth. In the description, the following abbreviations are used:
Combinations of substituents and variables envisioned by this invention are only those that result in the formation of stable compounds.
The term stable, as used herein, refers to compounds which possess stability sufficient to allow manufacture and administration to a mammal by methods known in the art. Typically, such compounds are stable at a temperature of 40xc2x0 C. or less, in the absence of moisture or other chemically reactive conditions, for at least a week.